US Army Corps of Engineers
Albuquerque District Website

I-Ditch Vicinity of Gate 20 (SPA-2012-00097-SCO)

Published Oct. 2, 2012
Expiration date: 10/23/2012

On March 13, 2012, the U.S. Army Corps of Engineers (Corps) Albuquerque District cited the Fort Carson Army Garrison for violation of Section 404 of the Clean Water Act (CWA) for the unauthorized discharge of dredged/fill material into waters of the U.S. associated with the relocation of approximately 700 linear feet (LF) of the I-Ditch stream channel. Subsequently, at the direction of the Corps, Fort Carson installed appropriate erosion control mechanisms to prevent further erosion of the I-Ditch channel. On August 28, 2012, Fort Carson submitted an after-the-fact permit application to the Corps for the realignment and permanent stabilization of the I-Ditch channel. Details of the proposed project are provided below and in the attached maps and drawings. The purpose of this public notice is to inform interested parties of the project and to solicit comments by the due date below.

Applicant: U.S. Army Garrison Fort Carson, Director of Public Works, 1626 Evans Street, Building 1219, Fort Carson, Colorado  80913.

Project Location: On the Fort Carson Army Garrison property in the I-Ditch channel in Section 23, T15S-R66W, Latitude 38.72351º N, Longitude -104.74238º W, El Paso County, Colorado.

Waterway: I-Ditch

Description of Work: The applicant proposes to realign approximately 700 LF of the I-Ditch channel. The new channel would be approximately 550 feet long, resulting in an increase in grade from 0.8% to 1.1%. In order to compensate for the resulting increase in erosion due to greater velocities, the applicant proposes to construct two riprap grade control structures and install a combined total of approximately 342 LF of rip-rap along the outsides of two bends. Each grade control structure would relieve between 0.5 and 1.0 foot of head and include a cobble apron extending a minimum of 20 feet downstream to function as a ramp to allow fish passage. In total, the project would require excavation of approximately 4,900 cubic yards of soil, including removal of most of the riparian vegetation, and placement of approximately 1,000 cubic yards (CY) of stone riprap and 120 CY of cobble. Approximately 700 LF of stream channel and 1,405 sq. ft. (0.03 acre) of riparian wetlands would be permanently impacted by this project.

Purpose and Need: The stated purposes of the project are to protect an existing access road, monitoring wells, and a storm sewer outfall structure from damages associated with the I-Ditch stream channel and to improve efficiency of stream flow through an existing trash rack and under the Fort Carson perimeter fence.

Mitigation: Compensatory mitigation for the permanent loss of approximately 0.03 acre of wetlands will be undertaken at a ratio of 1:1 concurrently with the project construction. All areas temporarily disturbed during construction and access will be revegetated using native seed mixes, as appropriate, for the areas disturbed. Weeds and other noxious plant species will be controlled post-construction in the project area until native communities are established.

Plans and Data: Drawings showing the location of the work site and other data are enclosed with this notice. If additional information is desired, it may be obtained from the applicant, or from:

Joshua G. Carpenter
U.S. Army Corps of Engineers
Southern Colorado Regulatory Office
200 South Santa Fe Avenue, Suite 301
Pueblo, Colorado  81003-4270
(719) 543-6914
Fax No. (719) 543-9475

Cultural Resources: The Corps has reviewed the latest published version of the National Register of Historic Places and no properties listed in the Register are present at the site of the proposed construction. Consultation with the Colorado State Historic Preservation Office (SHPO) has not revealed any pending nominations. This constitutes the extent of cultural resource investigations by the District Engineer. However, it is possible that presently unknown archeological, scientific, prehistoric, or historic data may be inadvertently lost or destroyed by the work accomplished under the requested permit. In the event that cultural resources are found, the permittee would be required to stop all work and the SHPO would be contacted for advice on the appropriate action to be taken.

Endangered Species: The Corps’ preliminary review indicates this project will not impact any threatened or endangered species or critical habitat.

State Water Quality Certification: The applicant has applied to the Colorado Department of Public Health and Environment for certification that this work is in compliance with applicable State water quality standards. The applicant is responsible for obtaining all other required federal, state, and local authorizations for this work.

Evaluation Factors: The decision whether to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts, of the proposed activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefit that may be reasonably expected to accrue from the proposal must be balanced against its reasonably foreseeable detriments. The evaluation of the impact of this activity will include application of the guidelines promulgated by the EPA Administrator under authority of Section 404(b) of the Clean Water Act. All factors relevant to the proposal and the cumulative effects will be considered; among these are conservation, economics, aesthetics, general environmental concerns, wetlands, historic properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shore erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, considerations of property ownership, and, in general, the needs and welfare of the people.

If the District Engineer determines that the project complies with the 404(b) (1) guidelines, he will grant the permit unless issuance would be contrary to the public interest.

In accordance with environmental procedures and documentation required by the National Environmental Policy Act of 1969, an environmental assessment will be prepared for this project. Upon completion, the assessment may be seen at the U.S. Army Corps of Engineers, Albuquerque District Office, at the address given above.

Comments: Any comments concerning this project should be received by the District Engineer no later than October 23, 2012. Comments received after the end of the public notice comment period will not be considered. However, more time may be given if a request, with a valid reason, is received prior to the suspense date. The Corps of Engineers is soliciting comments from the public; federal, state, and local agencies and officials; Indian tribes; and other interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps of Engineers to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this decision, comments are used to assess impacts on endangered species, historic properties, water quality, general environmental effects, and the other public interest factors listed below. Comments are used in the preparation of an Environmental Assessment and/or an Environmental Impact Statement pursuant to the National Environmental Policy Act. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.

Any person may request a public hearing. The request must be submitted, in writing, to the District Engineer within 21 days of the date of this notice and must clearly set forth the reasons for holding a public hearing.